(Toronto) The Canadian Cancer Society recommends people stick to existing daily limits on aspartame intake and encourages more study of the artificial sweetener after the World Health Organization (WHO) deemed it “ probably carcinogenic”.
The classification “means that there is little evidence to suggest that it can cause cancer in humans and that further research is needed,” said Elizabeth Holmes, director of health policy at the Canadian Cancer Society, during an interview on Friday.
Mme Holmes said the society welcomes aspartame research proposals and will consider funding them.
Two WHO-affiliated agencies conducted two independent reviews to assess the health risks associated with the consumption of aspartame, which is commonly found in diet drinks, gum, and sugar-free sweet treats like syrup or gelatin dessert.
By reviewing available human and animal studies, the International Agency for Research on Cancer (IARC) and the Food and Agriculture Organization of the United Nations Joint Expert Committee on Food Additives ( JECFA) found limited evidence that aspartame might be associated with a type of liver cancer. But the results could not exclude the possibility that other variables could explain this link.
Better studies, including randomized controlled trials, are needed to determine more definitively whether or not aspartame causes cancer, the study abstract states.
There was “no compelling evidence” to suggest that current recommendations on drinking or drinking aspartame safely should be changed, he said.
Both Health Canada and the WHO recommend a daily limit of 40 mg of aspartame per kilogram of body weight.
A WHO press release breaks it down: Since a can of diet soda contains about 200-300mg of aspartame, an adult who weighs 70kg would need to consume more than 9-14 cans a day to exceed this limit.
David Ma, a professor of nutritional sciences at the University of Guelph, said most Canadians’ daily aspartame intake is likely within that limit.
“Unfortunately, there are probably a few people who drink (above) that level. So these are the ones who should be most concerned about their consumption,” Ma said.
In an emailed statement, Health Canada said it would review the research and “determine whether action is needed for aspartame in Canada based on the scientific data contained in the full reports.”
The WHO has four classification levels for elements evaluated for their carcinogenic potential: carcinogenic to humans, probably carcinogenic to humans, possibly carcinogenic to humans and not classifiable as to its carcinogenicity to humans.
These levels are based on the strength of evidence that something, including food, drink, chemicals and environmental hazards, is linked to cancer.
Classification levels are not a statement of the “degree of risk” of developing cancer. The risk often varies with the amount consumed or levels of exposure. The type of cancer the food or drink is linked to also varies.
Tobacco, alcohol and processed meat are among more than 120 items currently classified as carcinogenic on the WHO website. There are over 90 items listed as “probable” carcinogens, including red meat.
As for “possible” carcinogens such as aspartame, over 320 items are listed. They include many chemicals, such as chloroform and lead.
It is important to consider substances listed as carcinogens, probable carcinogens or possibly carcinogens as “hazards” rather than “risks”, Ma said.
For example, driving a car is inherently dangerous, he illustrated. But the risk of injury is reduced by the actions we take.
“We accept this, because on a daily basis, millions and millions of people around the world drive. The risk is relatively low, because we put on our seatbelts, we respect the rules of the road, we do not drive dangerously at high speed,” elaborated Mr. Ma.
Likewise, aspartame is a “hazard”, but “the level of risk is low” if we don’t consume too much of it, he said.